Senior Test Engineer - Nuclear Systems (Onsite)

Radiant; El Segundo (CA); On-site; USD 150,000 - 210,000; Full time

Benefits offered by this job

Stock options

Medical coverage

8 weeks paid parental leave

Nuclear Engineering CertificateProgram

Daily catered lunch

Job summary

Radiant, an El Segundo, CA-based company building nuclear microreactors, seeks a Senior Test Engineer to drive test operations across development, qualification, and production acceptance of Kaleidos hardware. You will guide test strategies, execute fluid and thermal tests, and ensure data integrity in a fast-paced, safety-focused environment.

As Test Conductor/Director you will work with design engineers, author procedures to meet DOE/NRC-style standards, and mentor junior staff while

Qualifications

• 5+ years of full-time professional experience in engineering problem-solving, including system design, analysis, or testing.
• Bachelor’s degree in mechanical engineering or related field.
• Able to apply first principles thinking to solve problems in uncertain situations.
• Background in highly regulated industries (nuclear, aerospace, aviation, maritime).
• Experience leading projects and working independently.
• Strong fundamentals in fluids and thermodynamics.
• Strong written and verbal communication skills.
• Flexible and adaptable mindset with minimal direction.

Responsibilities

• Own and lead test strategy across development, qualification, and production acceptance phases.
• Plan and execute fluid, mechanical, and thermal tests on Kaleidos hardware from component to full system.
• Collaborate with design engineers to develop test methods and fixtures for fluid, mechanical, and electrical hardware.
• Integrate hardware into test setups: plumbing, instrumentation, data acquisition, and controls.
• Publish and maintain test procedures meeting DOE/NRC-aligned standards with clarity and usability.
• Identify risks and mitigations for pressurized/high-energy tests.
• Analyze test data and support root-cause investigations.
• Source test components and qualify suppliers for fabrication.
• Drive continuous improvement in test processes and data quality.
• Support one-off test campaigns in a fast-moving environment.

Skills

Engineering problem-solving

System design

Testing

First principles thinking

Project leadership

Fluids and thermodynamics

Communication

On-site adaptability

Education

Bachelor’s degree in Mechanical Engineering

Tools

Beckhoff

Python

MATLAB

NX CAD

Teamcenter

P&ID reading

Job description

Radiant, an El Segundo, CA-based company building nuclear microreactors, seeks a Senior Test Engineer to drive test operations across development, qualification, and production acceptance of Kaleidos hardware. You will guide test strategies, execute fluid and thermal tests, and ensure data integrity in a fast-paced, safety-focused environment.

As Test Conductor/Director you will work with design engineers, author procedures to meet DOE/NRC-style standards, and mentor junior staff while